<template>
  <div>
    <div class="mask" v-show="isShowSelect"></div>
    <el-popover placement="bottom-start"  :width="popoverWidth" :close-on-click-modal = "false"   trigger="manual"  v-model="isShowSelect" @hide="popoverHide">
      <el-tree class="common-tree" :width="width"   ref="tree" :data="treeData" :props="obj"
               :show-checkbox="multiple"
               :node-key="obj.id"
               :check-strictly="checkStrictly"
               :default-expanded-keys="defaultKeys"
               :expand-on-click-node="multiple&&expandClickNode"
               :check-on-click-node="checkClickNode"
               :highlight-current="true"
               @check-change="nodeClick"
               @node-click="nodeClick"
      ></el-tree>
      <el-select slot="reference" ref="select" :size="size" :width="width"
                 v-model="returnDataKeys"
                 :multiple="multiple"
                 :clearable="clearable"
                 :collapse-tags="collapseTags"
                 @click.native="selectClick"
                 @remove-tag="removeTag"
                 @clear="clean"
                 class="tree-select">
        <el-option v-for="item in options" :key="item.value" :label="item.label" :value="item.value"></el-option>
      </el-select>
      <!-- <el-row>
          <el-button v-if="multiple" class="ok" @click="isShowSelect=false" size="mini" type="text">确定</el-button>
      </el-row> -->
    </el-popover>
  </div>
</template>

<script>
export default {
  name: 'tree-select',
  props: {
    //绑定的值
    value: {
      type: String
    },
    // 树结构数据
    list: {
      type: Array,
      default () {
        return [];
      }
    },
    obj: {
      type: Object,
      required: false,
      default:()=>{
        return {
          id:'id',// ID
          label: 'name',// 显示名称
          children: 'children', //子级字段名
          path:'pathId',//路径
          content:'content',//描述
          pid:'parentId',//父id
        }
      }
    },
    // 配置是否可多选
    multiple: {
      type: Boolean,
      default () {
        return false;
      }
    },
    // 配置是否可清空选择
    clearable: {
      type: Boolean,
      default () {
        return false;
      }
    },
    // 配置多选时是否将选中值按文字的形式展示
    collapseTags: {
      type: Boolean,
      default () {
        return false;
      }
    },
    // 显示复选框情况下，是否严格遵循父子不互相关联
    checkStrictly: {
      type: Boolean,
      default () {
        return false;
      }
    },
    //多选是设置点击节点是否可以选中
    checkClickNode:{
      type: Boolean,
      default () {
        return false;
      }
    },
    //多选时：点击节点展开还是点三角标
    expandClickNode:{
      type: Boolean,
      default () {
        return false;
      }
    },
    // 默认选中的节点key
    // defaultKey: {
    //     type: [Number,String,Array,Object],
    //     default () {
    //         return [];
    //     }
    // },
    size: {
      type: String,
      default () {
        return 'small';
      }
    },
    width: {
      type: String,
      default () {
        return '100%';
      }
    },
    height: {
      type: String,
      default () {
        return '300px';
      }
    }
  },
  //上面是父组件可传入参数
  data () {
    return {
      defaultKeys: [],
      defaultKey: '',
      first: false,//
      popoverWidth:"0px",//下拉框大小
      isShowSelect: false, // 是否显示树状选择器
      options: [],//select option选项
      returnDatas:[],//返回给父组件数组对象
      returnDataKeys:[],//返回父组件数组主键值
    };
  },
  computed: {
    treeData() { // 若非树状结构，则转化为树状结构数据
      return   JSON.stringify(this.list).indexOf(this.obj.children) !== -1 ? this.list :  this.switchTree();
    },
  },
  methods: {
    init(){
      // eslint-disable-next-line no-undef,no-debugger
      if (this.multiple) {
        if(this.defaultKeys!=undefined && this.defaultKeys.length>0){
          // 多选
          if( Object.prototype.toString.call(this.defaultKeys).indexOf("Array")!=-1){
            if(Object.prototype.toString.call(this.defaultKeys[0]).indexOf("Object")!=-1){//对象
              this.setDatas(this.defaultKeys);
            }else if(Object.prototype.toString.call(this.defaultKeys[0]).indexOf("Number")!=-1
                || Object.prototype.toString.call(this.defaultKeys[0]).indexOf("String")!=-1){
              this.setKeys(this.defaultKeys);
            }else{
              console.log("多选：传入参数类型不匹配");
              return;
            }
          }else {
            console.log("多选：传入参数类型不匹配");
            return;
          }
        }
      } else {
        // 单选
        if( Object.prototype.toString.call(this.defaultKey).indexOf("Number")!=-1
            || Object.prototype.toString.call(this.defaultKey).indexOf("String")!=-1
            || Object.prototype.toString.call(this.defaultKey).indexOf("Object")!=-1 ){
          this.setKey(this.defaultKey);
        }else {
          console.log("单选：传入参数类型不匹配");
          return;

        }
      }
    },
    //下拉框select点击[入口]
    selectClick(){
      this.$nextTick(function () {//设置下拉框自适应宽度
        this.popoverWidth= this.$refs.select.$el.clientWidth-26;
      })
      //显示下拉框
      return this.isShowSelect = !this.isShowSelect
    },
    //单选: 树点击方法
    nodeClick (data, node) {
      if (!this.multiple) {//单选
        this.isShowSelect=false;
        this.setKey(node.key);
      }else{//多选
        var checkedKeys = this.$refs.tree.getCheckedKeys(); // 所有被选中的节点的 key 所组成的数组数据
        var t=[];
        this.options = checkedKeys.map((item) => {//设置option选项
          var node = this.$refs.tree.getNode(item); // 所有被选中的节点对应的node
          t.push(node.data);
          return {label:node.label,value:node.key};
        });
        this.returnDataKeys = this.options.map((item) => {
          return item.value;
        });
        this.returnDatas=t;
      }
    },
    //单选:清空选中
    clean () {
      this.$refs.tree.setCurrentKey(null);//清除树选中key
      this.returnDatas=null;this.returnDataKeys='';
      this.popoverHide ();

    },
    //单选:设置、初始化值 key
    setKey (thisKey) {
      this.$refs.tree.setCurrentKey(thisKey);
      var node = this.$refs.tree.getNode(thisKey);
      this.setData(node.data);
    },
    //单选：设置、初始化对象
    setData(data){
      this.options = [];
      this.options.push({label:data[this.obj.label],value:data[this.obj.id]});
      this.returnDatas = data;
      this.returnDataKeys=data[this.obj.id]

    },
    //多选:设置、初始化值 keys
    setKeys (thisKeys) {
      this.$refs.tree.setCheckedKeys(thisKeys);
      this.returnDataKeys = thisKeys;
      var t = [];
      //设置option选项
      thisKeys.map((item) => {
        //所有被选中的节点对应的node
        var node = this.$refs.tree.getNode(item);
        t.push(node.data);
        return {label:node.label,value:node.key};
      });
      this.returnDatas=t;
      this.popoverHide()
    },
    //多选:设置、初始化对象
    setDatas(data){
      this.$refs.tree.setCheckedNodes(data);
      this.returnDatas=data;
      var t=[];
      data.map((item) => {//设置option选项
        t.push(item[this.obj.id]);
      });
      this.returnDataKeys=t;
      this.popoverHide()
    },
    // 多选,删除任一select选项的回调
    removeTag (val) {
      this.$refs.tree.setChecked(val, false);//设置为未选中
      var node = this.$refs.tree.getNode(val);//获取节点
      if (!this.checkStrictly && node.childNodes.length > 0) {
        this.treeToList(node).map(item => {
          if (item.childNodes.length <= 0) {
            this.$refs.tree.setChecked(item, false);
          }
        });
      }
      this.nodeClick();
      this.popoverHide ();

    },
    //下拉框关闭执行
    popoverHide () {
      this.$emit('getValue', this.returnDataKeys, this.returnDatas);
    },
    // 多选，清空所有勾选
    clearSelectedNodes () {
      var checkedKeys = this.$refs.tree.getCheckedKeys(); // 所有被选中的节点的 key 所组成的数组数据
      for (let i = 0; i < checkedKeys.length; i++) {
        this.$refs.tree.setChecked(checkedKeys[i], false);
      }
    },

    //树形转为集合
    treeToList (tree) {
      var queen = [];
      var out = [];
      queen = queen.concat(tree);
      while (queen.length) {
        var first = queen.shift();
        if (first.childNodes) {
          queen = queen.concat(first.childNodes);
        }
        out.push(first);
      }
      return out;
    },
    switchTree() {
      return this.buildTree(this.list, this.defaultValue);
    },
    // 将一维的扁平数组转换为多层级对象
    buildTree(data, id) {
      const fa = (id) => {
        const temp = [];
        for (let i = 0; i < data.length; i++) {
          const n = data[i];
          if (n[this.obj.pid] === id) {
            n[this.obj.children] = fa(n[this.obj.id]);
            temp.push(n);
          }
        }
        return temp;
      };
      return fa(id);
    },

  },
  watch: {
    // eslint-disable-next-line no-unused-vars
    isShowSelect (val) {
      // 隐藏select自带的下拉框
      this.$refs.select.blur();
    },
    treeData(){//监听tree数据
      this.$nextTick(()=> {
        this.init();
      })
    },
    value: {
      handler (val) {
        this.$nextTick(()=> {
          if(this.multiple){
            this.defaultKeys = val
          }else{
            this.defaultKey = val
          }
          this.init();
        })
      },
      immediate: true
    },
    returnDataKeys: {
      handler (val) {
        if (this.first || val) {
          this.first = true;
          this.$emit('input', val);
        } else {
          this.first = true;
        }
      }
    },
  }
};
</script>

<style scoped>
.mask{
  height: 100%;
  position: fixed;
  top: 0;
  left: 0;
  opacity: 0;
  z-index: 11;
}
.common-tree{
  overflow: auto;
}
.tree-select{
  z-index: 111;
}
.ok{
  float: right;
}
.el-row{
  padding-top: 0 !important;
}
</style>

